Commitments, Contingencies, Guarantees, and Others - Schedule of Open Claims in Pipeline (Details) - Subsidiaries - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Unresolved Repurchase Claims [Roll Forward]
Open claims, beginning balance	$ 1,350	$ 2,512
Gross new demands received	13	46
Loans repurchased/made whole	(1)	(18)
Demands rescinded	(2)	(1,190)
Open claims, ending balance	1,360
Government-sponsored enterprises (“GSEs”)
Unresolved Repurchase Claims [Roll Forward]
Open claims, beginning balance	1	16
Gross new demands received	8	23
Loans repurchased/made whole	(1)	(17)
Demands rescinded	(2)	(21)
Open claims, ending balance	6
Insured Securitizations
Unresolved Repurchase Claims [Roll Forward]
Open claims, beginning balance	534	649
Gross new demands received	0	0
Loans repurchased/made whole	0	0
Demands rescinded	0	(115)
Open claims, ending balance	534
Uninsured Securitizations and Other
Unresolved Repurchase Claims [Roll Forward]
Open claims, beginning balance	815	1,847
Gross new demands received	5	23
Loans repurchased/made whole	0	(1)
Demands rescinded	0	$ (1,054)
Open claims, ending balance	$ 820